Certain fungi found in indoor environments, including homes and businesses, may cause adverse health effects in people and animals by provoking allergic reactions, causing infection, or releasing toxic substances. Recently, some attention has focused on the fungus Stachybotrys chartarum, which grows in moist indoor environments. Exposure to this fungus has been implicated in respiratory, dermatological, gastrointestinal, and central nervous system disorders in humans and a variety of animals. See, e.g., Fung, F., et al., Clinical Toxicology 36:79-86 (1998); Robbins, C. A., et al., Applied Occupational and Environmental Hygiene 15:773-84 (2000). For example, it has been suggested that Stachybotrys chartarum may be associated with “sick building syndrome,” an occupational condition in which workers are sickened by environmental toxins or pathogens. Craner, J., in: Bioaerosols, Fungi and Mycotoxins: Health Effects, Assessment, Prevention and Control, Johanning, E. (Ed.), (Eastern New York Occupational and Environmental Health Center, Albany, N.Y., 1999), pp. 146-157.
Exposure to the toxic substances, such as trichothecenes, or allergens produced by Stachybotrys chartarum is implicated in some respiratory disorders, including inflammation and hemorrhage of the lungs, and also may increase disease susceptibility in exposed subjects by affecting the inflammatory and immune responses after exposure. See, e.g., Dearborn, D. G., et al., Environmental Health Perspectives 107:495-99 (1999); Flappan, S. M., et al., Environmental Health Perspectives 107:927-930 (1999); Elidemir, O., Pediatrics 104:964-66 (1999); and Pitt, J. I., British Medical Bulletin 56: 184-92 (2000). However, the exact role of Stachybotrys chartarum in causing these adverse health effects is not well known and has been controversial, especially regarding human susceptibility to Stachybotrys chartarum. 
Accurate and precise monitoring methods are needed to better understand and analyze the role of Stachybotrys chartarum in certain diseases or conditions and the relevance of this fungus in causing or contributing to such health effects. Current methods of detecting this fungus rely on spore counts and cultivation of samples, which can be time-consuming and labor-intensive, or use chromatographic detection of specific mycotoxins, which can be insensitive and often requires specialized equipment. Therefore, a need exists for a method of assessing exposure to Stachybotrys chartarum that is rapid, accurate, and efficient.
If available, an antibody that binds to an antigen on a fungus may be used to detect some fungi. An antibody-antigen complex, formed when an antibody binds to an antigen, may be detected using a variety of techniques, such as the enzyme linked immunosorbent assay (ELISA), particle immunostaining, or fluorescence-based image analysis. For example, monoclonal antibodies against fungal allergens expressed by Alternaria alternata and several Aspergillus and Penicillium species have been used to identify and characterize environmental contamination. Chapman, M. D., et al., Clinical Reviews in Allergy and Immunology 18:285-300 (2000). The application of these monoclonal antibodies for measuring exposure was compromised by their cross-reactivity with other fungal species, variability or lack of essential expression of allergens recognized by the antibodies, or the lack of assay sensitivity due to low level production of allergens per unit biomass. Mitakakis, T. Z., et al., Journal of Allergy and Clinical Immunology 107:388-90 (2001); Vailes, L., et al., Journal of Allergy and Clinical Immunology 107:641-46 (2001). However, antibodies to Stachybotrys species, such as Stachybotrys chartarum, and associated methods of detecting these fungi were not previously known.